[FS] potential fix for heap poisoning.

Author: tschak909

lib/network-protocol/FS.cpp

@@ -190,7 +190,7 @@ bool NetworkProtocolFS::read(unsigned short len)
 
 bool NetworkProtocolFS::read_file(unsigned short len)
 {
-    uint8_t *buf = (uint8_t *)malloc(len);
+    buf = (uint8_t *)malloc(len);
 
     Debug_printf("NetworkProtocolFS::read_file(%u)\r\n", len);
 

lib/network-protocol/FS.h

@@ -30,6 +30,11 @@ class NetworkProtocolFS : public NetworkProtocol
      */
     bool rmdir_implemented = false;
 
+    /**
+     * Internal temporary buffer for read
+     */
+    uint8_t *buf;
+
     /**
      * @brief ctor
      * @param rx_buf pointer to receive buffer